1. Field of the Invention
The present invention relates to a keyboard of pianos and similar key instruments, for example grand pianos and harpsichords. The keyboard comprises a keyboard frame and a plurality of key arms arranged on bearing means in the keyboard frame in such a way that the key arms can be swinged only in a plane that is perpendicular to the plane of the keyboard frame.
2. Discussion of the Prior Art
For the present, keyboards of pianos and similar key instruments are manufactured substantially of wood. The keyboard frame as well as the key arms require a special kind of wood and a special pretreatment of the wooden pieces to be used. The key arms are sawed one after another from a carefully shaped key arm beam. This manufacturing method has several considerable disadvantages. First, the manufacturing is expensive, because a substantial effort of manual work is required for readjustment of pins and other bearings and of the key positions and this time consuming work has to be done by skilled craftsmen. Second, in spite of all the care taken during the manufacturing, the wooden pieces are affected during transportation and storing which makes further adjustments necessary in connection with the delivery to the purchaser. Third, the wooden pieces are affected by variations in temperature and air moisture which makes continuous adjustments necessary during the life of the keyboard.